Lightweight, plastic cervical collars come in a variety of designs. Traditional two-piece collars of the type shown in U.S. Pat. Nos. 3,756,226 and 4,886,052 use semi-circular body halves to provide cervical support. From the method disclosed by U.S. Pat. No. 3,622,057, the body halves are fabricated by shaping pliable cross-linked foam. Despite their acknowledged successful performance, such two-piece collars are considered less desirable than other cervical collars for certain uses. In particular, such collars are considered undesirable for use in emergency vehicles where their relative bulk makes them difficult to store and because of the difficulties that arise from trying to slip a semi-circular rear collar half beneath the neck of an accident victim at the same time the emergency care providers are trying to immobilize the victim.
A number of cervical collars have been designed to respond to this need. These include, for example, those shown in U.S. Pat. Nos. 4,413,619; 4,712,540; 4,987,891; 5,060,637; and 5,215,517. Such collars typically include unitary frontal and rear body sections cut from a non-foamed, relatively stiff, yet flexible plastic sheet. A hybrid cervical collar is shown in U.S. Pat. No. 5,083,553, has also been designed to respond to this need. The disclosed two-piece collar includes separate frontal and rear body sections cut from stiff, flexible plastic sheets.
The above-described collars are typically provided with an integrally attached chin support. This integrally attached chin support is either mechanically fastened to, or monolithically formed with the frontal body section, joining it at the distal ends of the chin support. However, the chin supports on such collars are typically provided as a flat structure, and must be folded into a cup-shape and mechanically fastened at the central portion of the folded frontal body section. This is due to the flat, resiliently flexible plastic sheet construction of the frontal body section and the chin support.
Thus, while certain cervical collars known in the prior art are easy to store and easy to position beneath the neck of an accident victim, it is believed that such collars do not provide the comfort and support provided by traditional two-piece, semi-circular designs.
Moreover, these prior art cervical collars all suffer from a number of drawbacks, especially with respect to the chin support area. Existing collars are fabricated from stiff, flexible plastic sheets requiring that the chin support be mechanically fastened to the frontal body section. This mechanical fastening results in inadequate chin support, lack of stability, and decreased reliability. Due to the fabrication process used for existing collars, there is inadequate support under the chin. This inadequate support causes the head of the wearer to slip from the chin support into the interior of the collar.
Another drawback is that existing fabrication processes typically necessitate a flexible chin support/frontal body section connection. Such connection requires the frontal body section at the chin support area to be bent at an angle to accept the chin support and a fastening. This weakened connection causes increased flexing and decreased rigidity of the chin support and results in an unstabilized cervical-spinal region of the wearer, which can potentially compound the wearer's spinal injuries. Also, during continual use, the mechanical fastenings typically employed to attach chin support to frontal body sections may fail and render the collar useless. Finally, the manufacturing costs associated with providing a mechanical fastening between the chin support and the frontal body section are relatively high due to the manual labor required to accomplish the fastening process.
Therefore, it is believed that there is a long-felt and as yet unsolved need for a substantially flat, one-piece and/or hybrid two-piece collar that can be stored more easily than conventional, semi-circular, two-piece collars but that provides more comfort and more support under the chin than provided by existing designs.
Accordingly, it is an object of the present invention to provide a flat cervical collar, that eliminates the need for a mechanical fastening at the central portion and distal ends of the chin support. It is also an object of the present invention to provide a flat collar that includes a rear or inner chin support ledge which captures the surface area under the region extending from the chin to each ramus of the mandible, thereby limiting flexing relative to the frontal body section and providing added stability to the cervical region.
It is a further object of the present invention to provide a process enabling the frontal body section and the chin support of a collar to be off unitary construction and a contoured three-dimensional configuration.
It is a another object of the present invention to provide a collar with a unitary chin support and a frontal body section construction that minimizes material, manufacturing, and assembly costs.
It is a still further object of the present invention to provide a flat, one-piece or hybrid two-piece, cervical collar fabricated by a process permitting the thickness of components to be independently varied to control the degree of rigidity and flexibility provided by each component.
Yet another object of the current invention is to provide a flat, one-piece or hybrid two-piece, cervical collar that includes mandible supports that can move independently of the frontal body section and each other to more readily adapt to the jaw line of a wearer.
A further object of the present invention is to provide a flat, one-piece or hybrid two-piece, cervical collar with living hinge connections at the distal ends of the mandible support that enable the mandible support to flex and conform to the jaw lines of collar wearers.
Each of the collars of the present invention described below satisfy at least some of these objects and all collars of the present invention collectively satisfy all of these objects.